Kondratev waves

Kondratev waves are 50-year periods of expansion and contraction in Western countries during the period from 1790 to 1940. These long-term business cycles were first observed and analyzed by the Russian economist and statistician Nikolay Kondratev. Kondratev’s analysis showed three cycles.

1. 1792–1815
2. 1850–1896
3. 1896–1940

The third cycle included expansion from 1896 to 1920 and then contraction from 1920 to 1940, the period of Joseph Stalin’s rule over the Soviet Union. This did not endear Kondratev to Russian leaders, and in 1928 he was dismissed from his post as director of the Institute for the Study of Business. He was later arrested, imprisoned, and received a death sentence. Business-cycle scholars have studied Kondratev’s work and developed a variety of hypotheses regarding these long-term waves, but no general consensus explanation has developed.